Some self-piercing rivets are used to join panels together without welding. The term “self-piercing” as used herein refers to a permanently installable rivet that has a piercing portion to pierce an opening in the panels to be joined. Some self-piercing rivets are used in mass production of products. Many instances of a self-piercing rivet may be installed in rapid succession from an automated installation head. For example, sheet metal panels may be joined with self-piercing rivets to form body parts of an automobile without welding.